The Kitchn: Old-fashioned buttermilk bar donuts are crispy, fluffy perfection
1 large egg
3 large egg yolks
3/4 cup buttermilk
About 2 quarts vegetable oil, for deep frying
For the vanilla glaze:
2 cups powdered sugar, sifted if lumpy
1 tablespoon vanilla extract
1/4 cup boiling water
Make the donuts:
1. Place 4 tablespoons unsalted butter in a small microwave-safe bowl. Microwave on HIGH until melted. Set aside to cool slightly.
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